Share-Based Payments - Schedule of weighted average assumptions for valuation of stock options (Details) - Employee Stock Option - USD ($) $ / shares in Units, $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Sep. 30, 2024 |
Sep. 30, 2023 |
Sep. 30, 2022 |
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| Weighted average assumptions relating to the valuation of stock options | |||
| Expected term (in years) | 6 years | ||
| Expected volatility | 48.70% | ||
| Risk-free interest rate | 1.20% | ||
| Dividend yield | 0.00% | 0.00% | 0.00% |
| Weighted average fair value of the stock options issued (in dollars per share) | $ 8.12 | ||
| Stock options awarded | 0 | 0 | |
| Aggregate fair value of stock options | $ 1.9 | $ 3.2 | $ 2.5 |
| Aggregate intrinsic value of options exercised | 0.7 | 1.4 | 4.0 |
| Proceeds from exercises of stock options | 1.8 | 1.9 | 8.1 |
| Tax benefit realized for the tax deductions of stock option exercises | 0.1 | $ 0.2 | $ 0.8 |
| Total unrecognized compensation expenses related to unvested awards | $ 0.1 | ||
| Weighted average period for recognition of unvested awards | 1 month 6 days | ||
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- Definition Amount of cost not yet recognized for nonvested award under share-based payment arrangement. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of tax benefit from exercise of option under share-based payment arrangement. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of cash inflow from exercise of option under share-based payment arrangement. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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- Definition The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The risk-free interest rate assumption that is used in valuing an option on its own shares. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Rate of weighted-average expected volatility for award under share-based payment arrangement. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Gross number of share options (or share units) granted during the period. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Details
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